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On this page (13 sections)
Schematic and BOM
1. Every component has a manufacturer part number. 2. Parts are in stock with more than one source where possible. 3. Polarity and pin-1 markings match datasheets. 4. Decoupling capacitors are present near every IC power pin.
Reviewing the BOM early with your manufacturer can reveal availability issues before layout begins.
Layout
5. Footprints match the exact package. 6. Trace widths suit the current. 7. High-speed signals have controlled impedance and short return paths. 8. Creepage and clearance meet voltage requirements. 9. Thermal pads have vias and relief where needed.
Running design rule checks with the fabricator's actual capabilities prevents files being rejected or boards failing.
Manufacturing and assembly
10. Fiducials are placed for automated assembly. 11. Components are kept clear of board edges. 12. Silkscreen does not overlap pads. 13. Panelisation and tooling holes are defined.
These details are easy to overlook but have a big effect on assembly speed and yield.
Testing
14. Test points are accessible for in-circuit and functional testing. 15. Programming headers are reachable after assembly.
Planning test access early makes production testing faster and more thorough.
Common mistakes we see
Wrong footprints for alternate packages, missing pull-up resistors, reversed connector pin-outs, inadequate copper for power paths and test points hidden under components are the most frequent issues found in design reviews.
Most of these issues are simple to fix in design but costly once boards have been fabricated.
Getting a second opinion
An independent DFM review before fabrication costs far less than a failed prototype round. We review layouts from other designers and provide a written report.
A fresh pair of eyes often spots issues the original designer has become too familiar to notice.
Documentation to send with Gerbers
Include a fabrication drawing with board thickness, material, copper weight, finish and tolerances; an assembly drawing with component orientation; a BOM with manufacturer part numbers; and pick-and-place data. Clear documentation avoids questions and delays.
Complete documentation also makes it easier to move production between manufacturers if needed.
Power integrity
Check that power planes and traces can carry the required current with acceptable voltage drop and temperature rise. Place bulk and decoupling capacitors where they are effective and keep high-current loops small.
Poor power integrity can cause intermittent faults that are difficult to diagnose later.
Thermal management
Identify components that dissipate significant heat. Use copper areas and thermal vias to spread heat, keep heat-sensitive parts away from hot components and consider airflow in the enclosure.
Thermal problems shorten component life, so addressing them in layout improves long-term reliability.
Mechanical checks
Verify mounting hole positions, connector locations and component heights against the enclosure using 3D models before release.
Checking fit early avoids costly enclosure or board changes after prototypes are built.
Silkscreen and markings
Include reference designators, polarity marks, pin-1 indicators, board name, revision and date. Clear markings help assembly, testing and repair.
Good markings reduce assembly errors and speed up field repairs.
Final release review
Before sending files, review the full package together: schematic, layout, BOM, drawings and fabrication notes. Check that revisions match across all documents.
A structured release review catches inconsistencies that individual checks may miss.
Need help?
Our engineers offer DFM reviews and complete PCB design services. Send us your files for a review.
We can review your design and provide a written report with recommended changes.